ABS-CBN Corporation, commonly known as ABS-CBN, is a Filipino media and entertainment group based in Quezon City, Philippines. It is the Philippines' largest entertainment and media conglomerate in terms of revenue, operating income, net income, assets, equity, market capitalization, and number of employees. ABS-CBN was formed by the merger of Alto Broadcasting System (ABS) and Chronicle Broadcasting Network (CBN). ABS was founded in 1946 by American electronics engineer James Lindenberg as Bolinao Electronics Corporation (BEC). In 1952, BEC was renamed Alto Broadcasting System (ABS), after Judge Antonio Quirino — brother of President Elpidio Quirino, who purchased the company. The company that would later be merged with ABS to form ABS-CBN was founded in 1956 as Chronicle Broadcasting Network (CBN) by newspaper mogul Eugenio Lopez, Sr. and his brother Fernando Lopez, which was then the Vice President of the Philippines. The two companies were merged and incorporated as ABS-CBN Broadcasting Corporation on 1 February 1967, and renamed ABS-CBN Corporation in 2010 to reflect the company's diversification. The common shares of ABS-CBN were first traded on the Philippine Stock Exchange in July 1992 under the ticker symbol ABS.